Detector



Aug. 18. 1925. 1,550,421

L. A. aoNlsH DETECTOR I 7 Filed April 27, 1922' Patented Aug. 18, 1925.

LEO A. BONISH, or DETROIT, MICHIGAN.

DETECTOR.

Application filed April 2'7, 1922. Serial No. 557,006.

To all whom it may concern:

Be it known that l, LEO BoNisH, a citizen of the United States of America, residin at Detroit, in the county of lVayne and tate of Michigan, have invented certain new and useful Improvements in Detectors, of which the following is a specification, reference being had therein to the accompanying drawings.

This invention relates to devices for holding the crystal for detectors used in connection with wireless receiving outfits, and the object of the invention is to provide a coir struction which is such that any portion of the surface of the crystal may be presented to the terminal or cat whisker to find the sensitive point and may thereafter be ad justed to give the proper contact and held in adjusted position to maintain contact with the sensitive point.

A further object is. to provide certain other new and useful features in the construction and arrangement of parts all as hereinafter more fully described.

With the above and other ends in view, the invention consists in the matters hereinafter set forth and more particularly pointed out in the appended claims, reference being had to the accompanying drawing', in which Figure 1 is plan view of a device illustrative of an embodiment of the invention;

Fig. 2 a side elevation of the same with a cup for holding the crystal shown in section; and

Fig. 3 is an end elevation.

As illustrative of a device suitable for use as a unit in a radio receiving outfit, the invention is embodied in a construction comprising a suitable rectangular base i upon which is mounted a spring arm 2 carrying a cup 3 at one end within which the crystal l is placed and secured in any suitable manner. The end of the spring arm 2 opposite that to which the cup is secured, is bent downwardly, as at 5, and the bent end portion secured to the base 1 by means of a suitable binding post 6 to which one of the wires of the electrical system is connected. A bracket 7 is secured to the base 1 by means of a binding screw 8 to which another of the wires of the electrical circuit is attached and this bracket extends upwardly and laterally and is formed with a horizontal end portion 9 provided with a screw-threaded opening to receive ascrew stem 10, the lower screw-threaded end portion of which extends through the arm 9 of the bracket and is engaged within the upper coils of a coiled spring 11., the lower end portion 12 of the wire forming this coil being extended downwardly to form acontact end or what is known as the cat whisker. This wire or cat whisker is therefore supported by the bracket in a position to engage within the cup 3 with its end in engagement with the crystal 4 therein. In order to find the sensitive point on the crystal, the cat whisker may be adjusted about the axis of the coil 11 by turning the screw 10 by means of an insulated knob 13 upon its upper end and when the proper adjustment of the cat whisker is secured. the screw 10 may be locked in such adjusted position by means of a lock nut 1+1: thereon adapted to engage the upper side of the arm 9 of the bracket. as the spring arm 2 is secured to the base 1 by a single point of attachment, that is, by the stem 15 of the post 6 which passes through a hole in the end of the arm and through an opening in the base, and said arm is free to swing laterally about its point of attachment to the base, and therefore the cup may be adjusted laterally relative to the cat whisker by swinging the arm which carries it. In this manner every part of the surface of the crystal may be engaged by the cat whisker and the sensitive point readily found.

\Vhen the sensitive point has been located, the contact between the end of the cat whisker and the crystal or the pressure with which the point engages the crystal may be very accurately adjusted by means of a thumb screw 15 which is ca ried by a bracket 16 secured in any suitable manner to the base 1 adjacent one side of the arm intermediate its ends by turning the screw by means of an insulating head 17 thereon. The force with which the cat whisker engages the crystal may therefore be very accurately adjusted without adjusting the screw 10 which carries the cat whisker and this is of vital importance in that if an adjustment of the cat whisker is attempted after the sensitive point of the crystal has been found, such adjustment is almost certain to be lost in an attempt to adjust the tension of engagement of the cat whisker with. the crystal. As the cat whisker is the end of the coil 11, said coil provides a yielding contact but this yielding; contact is further supplemented by the yielding action ten! of the swing arm 2 which carries the crystal. both the cat whisker and crystal are therefore yieldingly supported and the proper contact between the two may be very accurately adjusted by means of the adjusting screw which is arranged to defleet or depress the spring arm and when brought into contact with the spring arm frictionally holds this arm in the position to which it is adjusted so that the contact of the cat whisker with the sensitive point of the crystal will not be lost by any ordinary jars or jolts which the instrument may receive in use.

Gbviously the size and proportion of the parts and the particular arrangement shown may be varied within the scope of the an pended claims without depart from the spirit of the invention and 1 do not there fore limit myself to the exact construction shown.

What I claim as my invention is l. A device of the character described comprisin a base, spring; arm secured to the base, a crystal carried by the free end of said arm, a cat whisker supported for engagement with the crystal, means for ad 'ustin the cat whisker relative to the a: J

ta l, and means for adjusting said sprin arm to vary the contact pressure between said crystal and whisker.

2. A device of the character described comprising a base, aspring arm secured at one end to the base to yield vertically at its free end, a cup carried by the free end of said arm, a crystal in said cup, a bracket on the base extending over said cup and spaced therefrom, a cat whisker carried by said bracket to engage the crystal in said cup, a bracket on the base and extending over said arm intermediate the ends thereof, and an adjusting screw carried by said last named bracket to engage the upper side of the spring arm.

8. A device for the purpose described comprising a base, a spring arm pivotally secured at one end to said base with its free end portion spaced from and free to swing parallel with the surface of said base, a cup carried by the free end of said arm to receive a crystal, a crystal in said cup, a bracket on the base extending over and spaced from said cup, a rotatable adjusting screw carried by said bracket, a cat whisker carried by said screw with its cont-act end eccentric to the axis of rotation of said screw, and an adjusting screw to deflect said arm and adjust the free end thereof toward or from the base, to vary the force of contact between said crystal and whisker.

In testimony whereof I aifix my signature.

LEO A. BONISH. 

